RU72016U1 - GAS DISTRIBUTION STATION WITH ELECTRIC GENERATING DEVICE - Google Patents

Abstract

A gas distribution station with an electric generating device, characterized in that it has interconnected by means of piping with shut-off and control valves: a gas heater and boxes with technological units — a switching unit and a reduction unit, in which pulse gas preparation units are located with the inclusion of filters -dehumidifiers and shut-off elements, a cleaning unit with filters and a condensate storage unit, a gas flow measuring unit, an odorization unit, a unit for instrumentation and automation wherein, in the reduction unit, an expander-generator unit is installed, comprising a housing, inside of which: a generator, in the housing of which a stator, a rotor on the shaft, a power rectifier connected to the stator, a voltage regulator connected to the power rectifier; gas supply and exhaust pipes; a turbine in the form of an impeller with blades mounted on the rotor shaft, a nozzle apparatus in the form of three nozzles installed in the gas supply pipes and placed to the surface of the impeller blades at an angle of 8-30 °; the output to an external electrical network connected to the generator by means of an element of a cone-shaped conductor placed in the nozzle, a dielectric filler between the last and the conductor, while the element with the conductor is screwed out of the boss, rigidly fixed to the case of the expander-generator unit, the nozzle is installed junction box with a rubber seal, connected to the uninterruptible power supply battery and the heating system circulation pump.

Description

The utility model relates to the gas industry, namely to gas reduction equipment using the expander-generator technology for lowering gas pressure and is intended to reduce the high gas pressure of main gas pipelines to lower values required by gas consumers, with the associated generation of electricity through the use of gas differential pressure energy at the inlet and outlet of the gas distribution station (GDS).

Known automatic gas distribution station (AGRS) type "Source", designed to lower the pressure of the main gas before supplying it to consumers. AGRS contains a purification, switching and odorization unit, a gas reduction unit, an automatic gas heater, a control unit interconnected by inter-unit pipelines and cables [Product catalog of NPP Aviagaz-Soyuz + LLC, AGRS of Istok type, http: // www.agrs.ru/ p_istok.html]. The units are equipped with gas pollution sensors, fire alarms, heating and ventilation systems.

A disadvantage of the known AGRS is the low efficiency due to the fact that throttling is used to lower the gas pressure, during which the pressure energy of the transported gas is lost. In addition, part of the main gas is burned to heat the transported gas in order to prevent hydrate formation. The burning of fossil fuels and the release of combustion products into the atmosphere lead to an increase in the environmental load on the environment.

A gas distribution station with an electric generating device is also known [RU patent for utility model No. 47441], comprising a high pressure inlet pipe, a low gas pressure outlet pipe, a gas heater, an expander kinematically connected to an electric generator, a power transformer connected by a secondary winding to an electric network. The station further comprises a gas filter, a gas meter, a gas heater equipped with a voltage regulator, a frequency converter. The shafts of the expander and the generator are rigidly interconnected. The output of the generator is connected to the input of the frequency converter and through the voltage regulator with a gas heater, and the output of the frequency converter is connected to the input of the power transformer. The voltage regulator is made in the form of a controlled rectifier.

A gas distribution station with an autonomous power supply system is also known [RU patent No. 2270395], comprising a main valve, a gas pressure regulator, a turboexpander, a consumer main distribution valve, a coupling half-coupling and a synchronous generator connected to it. The turbo expander is designed according to the principle that uses useful energy released during the gas expansion process with a given pressure and temperature difference, in which the impeller with blades of a special profile sits on a cantilever shaft mounted on two bearings, and a connecting mating seal is located on the shaft end with a segmented self-sealing labyrinth seal coupling half. A control and protective shutdown unit is connected to the output of the synchronous generator while reducing the insulation resistance of the generator and consumers of electric energy, made in the form of a measuring circuit of the actuator connected to the network through a rectifier.

Also known gas distribution station with power generation [RU patent for invention No. 2221192]. The station is connected between the high-pressure main gas pipeline and the consumer low-pressure gas pipeline. The GDS contains electric machine turbine expanders, each of which includes a turbine and an electric generator located on its shaft, and at least one gas heater connected to the turbine inlet of at least one of the turbine expanders. The output of one of the turboexpander is connected to the consumer gas pipeline of final pressure. The output of the first or each of the other turboexpander is connected to the corresponding consumer intermediate pressure gas pipeline. Turbine expander power generators are made with voltage regulators and are connected through rectifiers to the battery station, to which the voltage inverter is connected.

The objective of the claimed utility model is to increase the reliability of the gas distribution station.

The essence of the claimed utility model is characterized by the fact that a gas distribution station with a power plant has interconnected by a strapping: a gas heater and boxes with technological units — a switching unit and a reduction unit, in which the pulse gas preparation units with the inclusion of filter driers are located in them and locking elements, a cleaning unit with filters and a condensate accumulator, a gas flow measuring unit, an odorization unit, a control instrumentation and automation unit; at

this in the reduction unit is installed an expander-generator unit, comprising a housing, inside of which: a generator, in the housing of which a stator, a rotor on the shaft, a power rectifier connected to the stator, a voltage regulator connected to the power rectifier; gas supply and exhaust pipes; a turbine in the form of an impeller with blades mounted on the rotor shaft, a nozzle apparatus in the form of three nozzles installed in the gas supply pipes and placed to the surface of the impeller blades at an angle of 8 ° -30 °; the output to an external electrical network connected to the generator by means of an element of a cone-shaped conductor placed in the nozzle, a dielectric filler between the last and the conductor, while the element with the conductor is screwed out of the boss, rigidly fixed to the case of the expander-generator unit, the nozzle is installed junction box with a rubber seal, connected to the uninterruptible power supply battery and the heating system circulation pump.

The technical result of the claimed utility model. The problem is solved by applying the technical technique, namely, introducing the expander-generator unit (DGA) of the specified design into the gas distribution station, which allows to ensure uninterrupted power supply from the battery supplied by the DGA to the automatic control and monitoring system and the heating system of the gas distribution system. The introduction of a voltage regulator and a power rectifier into the generator housing increases the stability of the parameters of the generated electricity. In addition, the claimed design of the conductor connecting the output of the generator to the external network allows for easy replacement of failed elements without replacing the hard connection in the form of a boss on the DGA housing, since the conductor is twisted out. The presence of a rubber seal in the junction box and a dielectric filler between the conical conductor and the fitting ensures the tightness of the DGA housing and prevents gas leakage. With the possible destruction of the dielectric filler in the element with a cone-shaped conductor, the housing does not completely depressurize, because under the influence of the gas flow pressure the conical shape of the conductor allows it to move forward to the inner surface of the nozzle and, like a plug, shut off the gas flow.

The implementation of the nozzle apparatus in the form of three nozzles fixed to the DGA housing, placed at an angle of 8 ° -30 ° to the surface of the impeller blades, makes it possible to most effectively use the energy of high gas pressure.

This angle is selected empirically from a number of values from the conditions of provision in starting mode without connecting the generator output to the load elements of the external network of the maximum number of revolutions of the generator shaft. Outside the angle, the following occurs. If the angle is less than 8 °, the incoming gas will not sufficiently spin the turbine blades, which will lead to a decrease in the speed of the generator shaft and, as a result, to a decrease in power generation.

The invention is illustrated using the drawings, which show: in Fig. 1 - the inventive GDS with an electric generating device, in Fig. 2 - an expander-generator unit, in which positions 1-23 indicate:

1 - block switching;

2 - cleaning unit;

3 - gas heater;

4 - block reduction;

5 - DGA;

6 - high-pressure natural gas pipeline;

7 - low-pressure natural gas pipeline;

8 - manometers;

9 - pressure regulator;

10 - gas cutoff;

11 - input locking element;

12 - output locking element;

13 - generator;

14 - gas supply pipes;

15 - pipe exhaust gas;

16 - turbine;

17 - output to an external network;

18 - stator;

19 - rotor;

20 - rotor shaft;

21 - power rectifier;

22 - voltage regulator;

23 - odorization block.

The inventive gas distribution system with a power plant is designed to reduce the high inlet pressure of natural gas to a predetermined low pressure and maintain

it with a certain accuracy when changing the gas flow rate and pressure at the station inlet, gas purification, measuring and recording gas flow, gas odorization.

GDS is cut off from the supply gas pipeline and the gas outlet pipelines by insulating flanges. Switching unit 1 consists of input, output and bypass lines. The bypass lines consist of a shut-off valve, a manual control valve, and a pressure gauge. The switching unit is connected to the gas odorization unit 23. As part of the switching unit 1, disconnecting ball valves with pneumatic drive are installed at the inlet and outlet gas pipelines. The cleaning unit 2 contains cleaning filters (working and standby), a condensate collection tank connected to the condensate accumulator by means of a pneumatic valve and a shut-off valve. The filtering element of the filter is a metal mesh with a cell of 40 microns. Liquid level sensors are installed in the condensate tank. The gas purification unit 2 also has a differential sensor connected to the purification filters. The pulsed gas preparation unit includes filter driers and shut-off elements.

The GDS contains a gas heater 3, connected to the reduction units 4 and switching 1, and a heater control unit. The heater connection unit 3 consists of two shut-off valves of the heater with a pneumatic drive, a bypass line of the heater with a pneumatic drive valve, a partial gas bypass line, with a pneumatic drive valve and a throttling device.

The gas flow measuring unit includes two flow measuring lines: a working and a backup, gas flow measuring devices, for example, quick-change narrowing devices, a gas meter with an electronic corrector connected to a gas heater.

Reduction unit 4 consists of two reducing lines: operating and backup, pressure regulators, which include safety shut-off valves. At the inlet of each reducing line, ball valves with pneumatic drive are located; at the exit, with manual transmission. Reducing lines connected to purge candles. The inlet and outlet pressures in the reduction unit are controlled by electric contact pressure gauges, and the pressure in each line is controlled by manometers, which are used to adjust the gas regulators.

To provide the automatic control system of the gas distribution system and the circulation pump of the heating system with electric energy, an expander-generator unit 5 (DGA) is installed in the reduction unit. The output from the generator 13 DGA is connected to the battery

batteries of uninterruptible power supply system of automatic control of GDS. The GDS also contains monitoring and control elements installed in the block of instrumentation and automation (instrumentation and automation). The box unit is heated from a gas-fired heating wall unit installed in the instrumentation box.

The expander-generator unit 5 comprises a vertically arranged housing made of a gas pipe closed from the ends by a bottom and a round-shaped lid connected by a flange connector. This housing design makes it possible to completely disassemble it, while simplicity of sealing the housing and high reliability of the detachable connection are ensured. The use of a lid and a bottom of a rounded shape provides a reduction in metal consumption and installation weight. DHA is connected on one side to a high-pressure natural gas line 6, including a pressure gauge 8, a pressure regulator 9 with a gas cut-off 10 installed therein in the form of a shut-off valve, an inlet shut-off element 11, and on the other hand, to a low-pressure natural gas line 7, including a manometer 8 and an output locking element 12. A generator 13, nozzles for supplying and discharging gas 15, a turbine 16, a nozzle apparatus, and a terminal 17 to an external electrical network are located inside the DGA 5 body. The generator 13 is a three-phase alternating current generator, in the housing of which there is a stator 18, a rotor 19 on the shaft 20, a power rectifier 21 connected to the stator 18, a voltage regulator 22 connected to the power rectifier 21. The turbine 16 is made in the form of an impeller with blades mounted on the shaft 20 of the rotor. The nozzle apparatus is made in the form of three nozzles installed in the gas supply nozzles and placed to the surface of the impeller blades at an angle of 8 ° -30 °, which form an angle of 120 ° in pairs with each other. The output 17 to an external electrical network is connected to the generator 13 by means of an element of a cone-shaped conductor placed in the fitting, between which and the conductor is a dielectric filler. The dielectric filler may be, for example, epoxy resin. The specified element is made unscrewed from the boss, rigidly mounted on the body of the DGA. This allows you to replace failed elements without replacing the rigid connection in the form of a boss. A junction box with a rubber seal is installed on the fitting, which ensures the tightness of the output of electricity.

The operation of the gas distribution system with a power plant is as follows. High pressure gas enters the input of the switching unit 1 GDS. After passing

the switching unit 1 gas is supplied to the cleaning unit 2 gas. Here, in the purification filters, the gas is purified from mechanical impurities and drip moisture. Mechanical impurities that have not passed through the grid and droplet moisture accumulate in the condensate accumulator. When the liquid reaches the upper level, a pneumatic valve opens and the liquid is discharged into the condensate collection tank. The liquid is discharged until it reaches the lower level, after which a command is issued to close the tap. If the valve does not close when the liquid reaches the lower level, the shut-off valve enters into operation, which closes when the flow of liquid through it stops and the flow of gas begins to flow. According to the readings of the differential sensor, the degree of contamination of the cleaning filters is estimated. The condensate collection tank is emptied by the crushing method. For this, a supply of natural gas from the gas reduction unit 4 for pressure is provided in the tank.

After cleaning, gas is supplied to the heater connection unit. With a total loading of gas distribution system up to 10000 m ³ / h (upon reaching a pressure drop of 0.1 MPa on the heater), a valve opens on the partial gas bypass line. When the flow rate decreases (when the pressure drop is less than 0.04 MPa), the valve on the partial gas bypass line closes.

Gas heating is carried out by heater 3 when monitoring the heater control unit based on ensuring the gas temperature at the outlet of the gas distribution station is not lower than + 5 ° С. After heating, gas is supplied to the gas flow metering units. Measurement of gas flow is carried out by narrowing quick-change devices. After measuring the flow rate, gas enters the reduction unit 4. When the pressure at the outlet of the pressure regulator reaches the upper or lower limits of operation, the safety shut-off valves automatically block the gas flow.

The backup line regulator is in the fully closed state during the normal operation of the station. In case of failure of the regulator and automatic blocking of the gas flow, the station switches to the backup line regulator. The outlet pressure is maintained at a slightly lower level by the backup line.

The control of the input and output pressures in the reduction unit 4 is carried out by electric contact pressure gauges, and the pressure control in each line is controlled by manometers, which are used to configure the gas regulators.

From the reduction unit 4, gas is supplied to the nozzle of the gas supply 14 on the housing of the expander-generator unit. In the DGA housing, gas enters through a nozzle apparatus,

where the potential energy of gas pressure transforms into the kinetic energy of gas motion. Next, the gas enters the blades of the impeller of the turbine 16. The turbine 16 with its rotation spins the rotor 19 of the generator. When the electromagnetic fields of the rotor 19 and the stator 18 interact, mechanical energy is converted into electrical energy. The alternating current obtained in this case is converted by a power rectifier 21 into a direct current voltage of 28 V, which is transmitted through an conductor to an external network. A fan installed on the rotor 19 creates a circulating gas flow inside the generator body 13, while the windings of the stator 18 and rotor 19 are cooled. To ensure stable voltage parameters of the network, a voltage regulator 22 is installed in the generator 13, which provides voltage regulation depending on changes in energy consumption. The gas passing through the impeller of the turbine 16 together with impurities is removed through the gas outlet pipe 15 located in the bottom of the DGA body 5.

After reduction, the gas enters the switching unit 1. On the inlet and outlet pipelines of the gas distribution system, valves with pneumatic drive are installed, which serve to shut off the gas distribution system in emergency situations and for repair. In this case, gas is supplied to consumers via bypass lines, each of which consists of a shut-off valve and a control valve with a manual actuator. Pressure reduction is carried out manually, the gas pressure at the outlet is controlled by a manometer.

After the switching unit 1, the gas is odorized in the odorization block 23, which provides a dosed odorant supply in proportion to the gas flow rate, while maintaining the possibility of odorization by the drip method. Replenishment of consumable containers of the odorant is done by squeezing the odorant from the storage capacity of the odorant. The odorization system equipment is made of corrosion-resistant steel.

To ensure autonomous operation of the automatic control and monitoring system, as well as the circulation pump of the heating system, backup power supply with a voltage of 24 V from the batteries (with automatic maintenance of them in a charged state from an external power supply), as well as from the expander - generator included in the reduction unit is provided unit with a voltage of 28 V.

Claims (1)

A gas distribution station with an electric generating device, characterized in that it has interconnected by means of piping with shut-off and control valves: a gas heater and boxes with technological units — a switching unit and a reduction unit, in which pulse gas preparation units are located with the inclusion of filters -dehumidifiers and shut-off elements, a cleaning unit with filters and a condensate storage unit, a gas flow measuring unit, an odorization unit, a unit for instrumentation and automation wherein, in the reduction unit, an expander-generator unit is installed, comprising a housing, inside of which: a generator, in the housing of which a stator, a rotor on the shaft, a power rectifier connected to the stator, a voltage regulator connected to the power rectifier; gas supply and exhaust pipes; a turbine in the form of an impeller with blades mounted on the rotor shaft, a nozzle apparatus in the form of three nozzles installed in the gas supply pipes and placed to the surface of the impeller blades at an angle of 8-30 °; the output to an external electrical network connected to the generator by means of an element of a cone-shaped conductor placed in the nozzle, a dielectric filler between the last and the conductor, while the element with the conductor is screwed out of the boss, rigidly fixed to the case of the expander-generator unit, the nozzle is installed junction box with a rubber seal, connected to the uninterruptible power supply battery and the heating circulation pump.